Custom Letter Numbering

[binar]

Fellow Forum Members,
Word 2007 has the following letter numbering flow built in:

a.
b.
c.
(skipping d. through t.)
u.
v.
w.
x.
y.
z.
aa.
bb.
cc.
dd.
ee.
(skip)
zz.

Is it possible for WORD to follow the letter numbering format shown below instead?

aa.
ab.
ac.
ad.
(skip)
az.

In other words the "a" stays the same until "z". After "z" is reached the format changes to:

ba.
bb.


bc.
bd.

Then after "z" is reached again the format changes to:

ca.
cb.
cc.
cd.

This numbering scheme doesn't seem to be included in WORD 2007. Is it possible for WORD 2007 to some how support this numbering format? Any info will be greatly appreciated. Thanks.

[macropod]

You can't do this with Word's inbuilt numbering scheme, but you could use a set of SEQ fields like:
{QUOTE{SET A2Z{=MOD({SEQ ABC}-1,26)+1}}{SET AA2ZZ{=INT(({SEQ ABC \c}-1)/26)}} {IF{AA2ZZ \* ALPHABETIC}= " " "" {AA2ZZ \* ALPHABETIC}}{A2Z \* ALPHABETIC}}
This will produce the sequence: A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z, AA, AB, AC, AD, AE, AF, AG, AH, AI, AJ
Note: The field brace pairs (ie '{ }') for the above example are created in the body of the document via Ctrl-F9 (Cmd-F9 on a Mac) - you can't simply type them or copy & paste them from this message.